Blake Mycoskie is an entrepreneurial spirit at heart: he started the first of many companies at the tender age of 18. “But it wasn’t really until I started TOMS that I felt like I had my calling,” he says. The shoe company, founded in 2006, utilizes a One to One business model that donates a pair of shoes to a child in need for every pair that a consumer purchases. Mycoskie spoke to TIME about how he applies his business acumen in service of a compassionate mission.

When we started TOMS six years ago, a lot of people asked, why shoes? Why is it so important? Children need shoes to go to school as part of their uniform requirements, children need shoes to protect their feet from disease, and people could internalize that. But it wasn’t until we said, you try going one day without shoes and see what the experience is like. That really brought it home to people. People [who participated] would get all different types of questions; they would get treated differently. Their feet oftentimes would be tired and sore after a day without shoes. We found this is a really great way for people to raise awareness for the millions of people around the world who don’t have a choice but to go barefoot every day.

Do you have any advice for urban dwellers who want to participate but are apprehensive about, say, riding the subway shoeless?

You don’t have to go shoeless all day long. Wear your shoes—preferably your TOMS—to work that day, or to school or to wherever you’re going, and when you get there you can participate inside. It’s just as effective to walk around your office or in your cafeteria or in the grocery store barefoot, cause that’s going to get just as many people asking about it, which is the whole purpose.

Why did you choose to found TOMS as a for-profit business instead of a charity?

When I first met these children in South America who didn’t have shoes, I wanted to give them the shoes that they needed to go to school. I recognized that giving them shoes once or even twice was not really going to be effective. They needed a commitment of shoes on an ongoing basis, over and over again. A charity is really dependent on donations, and sometimes donors don’t always show up. They have a good year, they have a bad year—it changes their ability to give on a year-by-year basis. But as a business, there’s a lot more stability, especially if you build a successful business. And that allows us to have sustainability.

How did you decide to expand TOMS into eyewear?

As we started looking around the different communities we served, we recognized that there were many kids that could not see the chalkboard and were not getting the education and getting treated differently, and sometimes being misdiagnosed that they have a learning disability when really they just couldn’t see. At the same time, we saw a lot of elderly people developing cataracts and that having a detrimental impact on their families as well. So when we learned that there were these amazing nonprofit organizations helping with cataracts and prescription glasses and eye treatments, and we could build their cost into the cost of selling sunglasses—that we really could take the One for One model into another way—we got really excited about it. We’ve helped over 150,000 people get their sight back, and that’s growing every day. It’s such a significant thing when you see someone who is blind one day and then 48 hours later they’re seeing their grandchildren for the first time.

How many pairs of TOMS would you say that you own yourself?

Surprisingly, I don’t usually have more than five or six pairs in my closet at a time. They give me all the newest shoes that they’re creating so that I can test them out first. And then they want them back so they can see how well they wore or what my feedback was. So I’m constantly wearing different pairs, but it’s not like I have a closet of hundreds of pairs. I think there are some people out there that do.